Arthropod Predation of Vertebrates Structures Trophic Dynamics in Island Ecosystems

Abstract

On isolated islands, large arthropods can play an important functional role in ecosystem dynamics. On the Norfolk Islands group, South Pacific, we monitored the diet and foraging activity of an endemic chilopod, the Phillip Island centipede (Cormocephalus coynei), and used a stable isotope mixing model to estimate dietary proportions. Phillip Island centipede diet is represented by vertebrate animals (48%) and invertebrates (52%), with 30.5% consisting of squamates, including the Lord Howe Island skink (Oligosoma lichenigera) and Günther's island gecko (Christinus guentheri); 7.9% consisting of black-winged petrel (Pterodroma nigripennis) nestlings; and 9.6% consisting of marine fishes scavenged from regurgitated seabird meals. Centipede predation was the principal source of petrel nestling mortality, with annual rates of predation varying between 11.1% and 19.6% of nestlings. This means that 2,109-3,724 black-winged petrel nestlings may be predated by centipedes annually. Petrels produce a single offspring per year; therefore, predation of nestlings by centipedes represents total breeding failure for a pair in a given year. Our work demonstrates that arthropods can play a leading role in influencing vertebrate reproductive output and modifying trophic structures and nutrient flow in island ecosystems.

Investigating the impact of black rats (Rattus rattus) on the endemic and threatened avifauna of Christmas Island

“…Nest cameras inadvertently recorded a giant centipede preying upon a thrush chick; an impact previously undescribed on Christmas Island. On Phillip Island, New South Wales, native centipedes were the principal source of black-winged petrel ( Pterodroma nigripennis ) nestling mortality, with annual rates of predation varying between 11.1% and 19.6%, equating to 3724 nestlings (Halpin et al . 2021).…”

Terrestrial subsidies and light affect an aquatic micro‐ecosystem in unexpected ways

“…Most of Earth's ecosystems are connected to each other by an intricate web of interactions. Some of these interactions happen when organisms interact across the boundaries of neighbouring ecosystems, for example through direct predation (Marczak et al, 2007;Paine, 1934) or indirect trophic interactions (Halpin et al, 2021;Knight et al, 2005).…”

“…Most of Earth's ecosystems are connected to each other by an intricate web of interactions. Some of these interactions happen when organisms interact across the boundaries of neighbouring ecosystems, for example through direct predation (Marczak et al., 2007; Paine, 1934) or indirect trophic interactions (Halpin et al., 2021; Knight et al., 2005). Other interactions between ecosystems consist of fluxes of matter, often on vast scales, when, for example, dust from the Sahara is carried by atmospheric currents and fertilises bromeliads in the Caribbean (Royer et al., 2018), or when El Niño events over the equatorial Pacific Ocean affect precipitation over eastern Africa (Sinclair et al., 2013).…”

Genetic diversity and gene flow of the soil arthropod (Scolopendra mutilans) in urban landscapes: The roles of rivers, mountains and fragmentation

“…However, a few studies have focused on highly motile soil invertebrates such as centipedes, which are a large carnivorous species. This group is the top predator among soil invertebrates, which plays a critical role in the food webs of soil ecosystems (Halpin et al, 2021). Scolopendra mutilans is spread all across China (Han et al, 2018; Ren et al, 2005) and comprises the most common and largest centipede species in the middle and lower reaches of the Yangtze River, which contributes to the stabilisation of local soil ecosystems (Ren et al, 2005; Zhang & Wang, 1995).…”